iPad's touch keyboard covers more than half its screen, obscuring most of what you compose. Bluetooth keyboards from Logitech and iLuv are designed to free up iPad screen real estate and make it easier to compose text. I've had a chance to play with them and here are my impressions.
As with the Kensington KeyFolio, you can flip the iLuv keyboard around to use the iPad as a tablet. There are notches on either side for the front-facing camera and the Home key; there's a hole in the back cover for the rear camera. Just make sure to turn the iLuv off before you flip the keyboard around and flop it keys down on your lap.